Attempts to produce an effective anti-theft device or safety lock for motor vehicles have been undertaken for a long time. Representative patents showing such devices or locks include:
U.S. Pat. No. 1,040,509--Cleveland PA1 U.S. Pat. No. 1,217,719--Dorgan PA1 U.S. Pat. No. 1,582,528--Michael PA1 U.S. Pat. No. 3,358,481--Roszkowski PA1 U.S. Pat. No. 3,630,306--Shur PA1 U.S. Pat. No. 3,682,267--Kayser PA1 U.S. Pat. No. 3,720,284--Myers PA1 U.S. Pat. No. 3,750,430--Crisa PA1 U.S. Pat. No. 3,773,139--Landi PA1 U.S. Pat. No. 3,855,828--Verderber PA1 U.S. Pat. No. 3,879,969--Pynn PA1 U.S. Pat. No. 3,968,666--MacKinnon
These patents show a variety of devices or locks which range from very complex to relatively simple structures possessing a multitude of ways of basically preventing someone from by-passing the ignition system and/or effecting gas flow from the gas tank to the carburetor. These patents, however, do not describe an anti-theft device which has features of the present invention.